xgboost::ObjFunction Class Reference

interface of objective function More...

#include <objective.h>

Inheritance diagram for xgboost::ObjFunction:

Collaboration diagram for xgboost::ObjFunction:

Public Member Functions
	~ObjFunction () override=default
	virtual destructor More...
virtual void	Configure (const std::vector< std::pair< std::string, std::string > > &args)=0
	Configure the objective with the specified parameters. More...
virtual void	GetGradient (const HostDeviceVector< bst_float > &preds, const MetaInfo &info, int iteration, HostDeviceVector< GradientPair > *out_gpair)=0
	Get gradient over each of predictions, given existing information. More...
virtual const char *	DefaultEvalMetric () const =0
virtual void	PredTransform (HostDeviceVector< bst_float > *)
	transform prediction values, this is only called when Prediction is called More...
virtual void	EvalTransform (HostDeviceVector< bst_float > *io_preds)
	transform prediction values, this is only called when Eval is called, usually it redirect to PredTransform More...
virtual bst_float	ProbToMargin (bst_float base_score) const
	transform probability value back to margin this is used to transform user-set base_score back to margin used by gradient boosting More...
Public Member Functions inherited from xgboost::Configurable
virtual	~Configurable ()=default
virtual void	LoadConfig (Json const &in)=0
	Load configuration from JSON object. More...
virtual void	SaveConfig (Json *out) const =0
	Save configuration to JSON object. More...

Static Public Member Functions
static ObjFunction *	Create (const std::string &name, GenericParameter const *tparam)
	Create an objective function according to name. More...

Protected Attributes
GenericParameter const *	tparam_

Detailed Description

interface of objective function

Constructor & Destructor Documentation

~ObjFunction()

xgboost::ObjFunction::~ObjFunction ( )

overridedefault

virtual destructor

Member Function Documentation

Configure()

virtual void xgboost::ObjFunction::Configure ( const std::vector< std::pair< std::string, std::string > > &  args )

pure virtual

Configure the objective with the specified parameters.

Parameters

args	arguments to the objective function.

Create()

static ObjFunction* xgboost::ObjFunction::Create ( const std::string &  name, GenericParameter const *  tparam  )

static

Create an objective function according to name.

Parameters

tparam	Generic parameters.
name	Name of the objective.

DefaultEvalMetric()

virtual const char* xgboost::ObjFunction::DefaultEvalMetric ( ) const

pure virtual

Returns

the default evaluation metric for the objective

EvalTransform()

virtual void xgboost::ObjFunction::EvalTransform ( HostDeviceVector< bst_float > *  io_preds )

inlinevirtual

transform prediction values, this is only called when Eval is called, usually it redirect to PredTransform

Parameters

io_preds

prediction values, saves to this vector as well

GetGradient()

virtual void xgboost::ObjFunction::GetGradient ( const HostDeviceVector< bst_float > &  preds, const MetaInfo &  info, int  iteration, HostDeviceVector< GradientPair > *  out_gpair  )

pure virtual

Get gradient over each of predictions, given existing information.

Parameters

preds	prediction of current round
info	information about labels, weights, groups in rank
iteration	current iteration number.
out_gpair	output of get gradient, saves gradient and second order gradient in

PredTransform()

virtual void xgboost::ObjFunction::PredTransform ( HostDeviceVector< bst_float > *  )

inlinevirtual

transform prediction values, this is only called when Prediction is called

Parameters

io_preds

prediction values, saves to this vector as well

ProbToMargin()

virtual bst_float xgboost::ObjFunction::ProbToMargin ( bst_float  base_score ) const

inlinevirtual

transform probability value back to margin this is used to transform user-set base_score back to margin used by gradient boosting

Returns

transformed value

Member Data Documentation

tparam_

GenericParameter const* xgboost::ObjFunction::tparam_

protected

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The documentation for this class was generated from the following file:

• /home/runner/work/xgboost/xgboost/include/xgboost/objective.h